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Trunnion question

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doughairfield

doughairfield

Jedi Trainee
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I'm on the home stretch of putting new trunnions on my 64 TR4, but I've got one question.

On the lower A-Arms, trunnion end, there is a locking washer that is the final piece you put on before the slotted nut, but it's inner diameter is too small to slide over the "arm" of the trunnion. Do you have to ream these locking washers to fit as you do the A-Arm bushings, or do they just press in forming a seal once you tighten the slotted nut down?
 
They press in, and basically lock in place that way. But be careful, some aftermarket washers are really tough, or perhaps a little too small. If it takes excessive force to work the washers on with the nut - don't force it. A friend of mine did and broke the trunnion. His fix was to buy from another supplier (sorry don't recall good source vs bad). I suspect another way would be to ream out the washer slightly until its close to going on.
 
Thanks for the info Randy.

I bought the kit from TRF. The washer sort of fits on the trunnion. I opted to use a normal nut to tighten the washer on the trunnion arm instead of the slotted one since they are not as strong. The nut and washer started going on there but as it took more and more force to tighten the nut, I chickened out and decided i'm going to ream the one for the other side and see how that goes instead of forcing it on.
 
Ok, got the lock washers on the trunnion arms, wasn't too bad.

When I put the castellated nut on the trunnion, and tighten it up to the lock washer, the nut is too far past the hole drilled in the threaded part of the trunnion for the cotter pin to properly lock the nut in place. Is it acceptable to put a washer in-between the castellated nut and the lock washer to get the castellated nut in the right position?
 
My guess is it may not be a problem with an extra washer, but its likely not optimum. I think the culprit could be the thrust washers that are supplied with the fitting kits now - I've seen and owned some that are basically too thin, thinner even than the worn originals, so when everything is made up I think you could get the situation you describe.

My only worry with what you suggest is that the lower arms are potentially pulled in further than they should be, so you may see early wear at the pivot areas, or worse, potentially binding. I'm not going to swear by it, but I think the Moss thrust washers are thicker based on my memory.
 
What you're saying about the thrust washers makes. I gotta say, the idea of pulling that whole suspension assembly apart again and changing those washers out isn't very tempting.
 
I guess I'll have to order new thrust washers from moss to see if they are actually thicker than the ones from TRF
 
Doug-

I should have also said, if its not noticeably binding, maybe just don't worry about it - yes, pulling it apart is a major pain in the backside. I do know I fit TRF trunnions recently and picking through the thrust washers I had I was able to use castle nuts to finish it off with cotter pins - so I'm suspicious of those thrust washers.

Randy
 
I racked my brain over trunnions this weekend...(See my other posts).

There should be a separate forum just for Trunnions!
 
doughairfield said:
Ok, got the lock washers on the trunnion arms, wasn't too bad.

Hi There Doug,

I`m at exactly the same stage. Did you Ream the Lockwashers? Also; When you tighten the lockwasher down onto the spline; Does this "Have To" be done at Assy or can you do it before Assy? Meaning, Take the Trunnions and clamp them into a Vise & tighten down on the Lockwashers?

Thanx, Russ
Click to expand...
 
Hey Russ,
I did not ream those Lockwashers, although the thought did cross my mind. I was worried I would ream a little too much and they they would be loose or allow dirt to get in there.

I greased the washers up pretty well, then used a large nut and flat washer to force the lockwasher onto the arm of the trunnion. I would NOT recommend using the castellated nut to do this as I don't think they are nearly as strong as a regular nut. Additionally, I tried to find a nut that was fairly tall so it would have the max amount of purchase on the most number of threads on the trunnion to prevent stripping anything out.

I did all this on the car. Meaning I didn't put the trunnions and A Arms into a vise.

Good Luck.
 
FWIW- I just "forced" the slotted washer onto the trunnion pin end (I did use the castle nut for primary torque) and all went together fine.

I cannot remember the exact torque #, but tightened the nut to that and then backed off a half flat to line up the castle with the pin hole.

Finally it was suggested elsewhere (on a post) to use a mallet on the backside of the each A arm (two per side) and bang the a-arm outward so as to "loosen up" the full assembly. This was effective in making the whole assembly freely move up and down (with some minor force required).

FYI - my trunnion bodies and pins are all OEM and refurbished by yours truly (as opposed to new reprop). However, the lock washers are new from Moss.

w
 
Also FWIW, I believe the ends of the splines on the pivot should have a bit of a taper to them, to make it easier to force the washer on the first time. Some of the reproductions don't have the taper, making it much harder to force (and deform) the washer.

One solution is to grind the taper; another is to use the old trunnions to deform the new washers.
 
Howdy Folks,

Well; I pretty much have the Front Suspension Assembled on my TR3 and all went quite well.

I have the "Trunnion Grease Seals" but something seems wrong or ???

The Seals are a "C" type configuration (Look like a small tire) & The "ID" is considerably larger than the "Thread & Shaft OD" on the Vertical Link. How is this supposed to go together to prevent Grease from coming out of the top of the Trunnion? Some close up pics would really be appreciated & or Suggestions.

Also; I have a "Grease Seal" for the "Idler Arm" Assy. I rec`d. what looks like a simple "O Ring". The O-Ring fits snuggly over the Threaded & Shaft part of the Arm itself but it sure does`nt seem like it would hold any Grease from coming out of the top of the Housing. Again, Suggestions, Pics For Sure would be Outstanding!!

If your like me & can`t, (Don`t want to), shrink pics to post here; Please email to: toysrrus@att.net.

Thanx in Advance,

Russ
 
The trunnion seals don't fit snugly around the threaded part of the shaft, but instead seal between the top of the trunnion and the flat area on the vertical link. They don't really seal the grease in, more like keep the dirt out.

The idler arm seal should be similar; sounds like you got the wrong part.

Sorry I don't have a good photo to share, but you can see a little bit of the idler seal here

DSCF0031crop.jpg
 
I don't believe anyone has brought this up, and you probably know this already, BUT, you don't want to use grease in your trunnion due to the potential of it getting compacted and hardening over time. At least that is my understanding anyway.

I think the preferred lubricant is 90W gear oil. There was a thread a while back about what the best method of getting said oil into your trunnion was, but I can't seem to find it.
 
I've heard a combination of "some" grease AND 90w (GL4) hypoy oil is the proper lubrication for the trunnions. The thought behind it that the hypoy oil will keep the grease soft long term. ...and that you should at least annually add oil to the trunnions.
 
There are different trunnions used on TR2-6; the early ones take grease, the later ones take oil. IMO TR3 trunnions should be greased as they tend to leak oil. And as long as you add fresh grease every decade or so, you're not likely to have any trouble with modern grease drying up. (Obviously it's desirable to service them more often than every decade; I try to do them every year or two whether they need it or not :smile: )
 
Willie_P said:
I've heard a combination of "some" grease AND 90w (GL4) hypoy oil is the proper lubrication for the trunnions.
Click to expand...

And the grease has to be taken from a black chicken killed at midnight.
 
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